The present invention relates to a protective cap for enclosing the needle of a hypodermic syringe which may or may not be intended for medical use.
At the present time, a cap of this type is designed in the form of an elongated hollow body of circular cross-section, one end of which is closed whilst the other end is open so that it can be frictionally engaged on the conical sleeve provided at the lower end of the needle to be covered for the purpose of fixing it on the discharge nozzle of a syringe. Caps of this type can thus be readily removed when using the corresponding needles. However, they are intended to be put back in place after the needles have been used in order to guard against any danger of injury to a third party and above all any danger of contamination by the blood of the person who has been subjected to an injection, especially any danger of contamination by AIDS or serum hepatitis, etc.
However, the re-introduction of a hypodermic needle into a cap of this type is very difficult. In fact, the operator has to hold the cap with one hand while the syringe which carries the spent needle is held with the other hand. He then has to engage the end of this needle within the cap, or conversely. However, this operation is very awkward and the operator is very often unable to engage the needle within its cap. In point of fact, a faulty handling operation may result in accidental pricking and therefore in a risk of contamination of the operator. Under these conditions, members of medical staffs are more and more inclined to omit replacement of protective caps on hypodermic needles, thus entailing risks of contamination of third parties.
In an attempt to solve this problem, U.S. Pat. No. 4,643,722 relates to a protective cap having a slit which extends practically over its full length from its open end. This slit is intended to permit introduction of a needle on one side and not at the end. However, this is not sufficient to solve the problem at issue. In fact, in order to introduce a syringe needle into a cap of this type, the operator again has to hold this latter with one hand while holding with the other hand the syringe which carries the spent needle. In consequence, there is still a considerable danger of accidental pricking which arises simply from the fact that the operator has to hold the cap with one hand while inserting the needle in this latter.
Another problem which is not satisfactorily solved by U.S. Pat. No. 4,643,722 is that of complete enclosure of a spent needle within its protective cap. In fact, in order to remove any danger of contamination, the needle must be perfectly secured and completely enclosed within its protective cap. Now in order to close the longitudinal slit, U.S. Pat. No. 4,643,722 simply proposes to close the longitudinal needle-insertion slit by means of a member which is subsequently fitted on said slit. Positioning of this closure member is again a potential cause of accidental pricking of the operator if the needle moves during this operation. Moreover, the addition of a closure member of this type is a cause of complication, not only in regard to the operations to be performed but also in regard to the manufacture of the protective cap and its cost price which must remain extremely low.
For the reasons given in the foregoing, the present invention is directed to a protective cap which is intended to serve the same purpose but which is designed with a view to avoiding the disadvantages recalled above and in particular the risks of contamination of a medical practitioner or of a third party.